The present invention relates to a device for preventing sticking of weighed material in an automatic weighing apparatus. More particularly, the invention is concerned with a device for preventing comparatively viscous weighed material such as boiled beans, pickles or the like from adhering to the constituents of an automatic weighing apparatus such as trough, hopper, chute and so forth.
Generally, a combined weighing apparatus incorporating a computer, referred to as "computer scale", is used for accurately weighing materials which exhibit large variation or fluctuation of weight, e.g. fruits and vegetables, confectionaries, secondary products, perishables or the like.
In such a combined weighing apparatus, batches of the material to be weighed are put into a plurality of weighing hoppers and weighed in respective hoppers. Then, the apparatus selects a combination of batches which provides a total weight closest to the command weight within a predetermined tolerance. The batches constituting the selected combination are then discharged and the evacuated weighing hoppers are charged with new batches of the material for the next weighing operation. This operation is repeated to achieve the automatic weighing of the material.
Objects such as boiled beans, pickles or the like contains liquids of comparatively high viscosity and, hence, are sticky. When such materials are weighed by a combined computer scale, the materials undesirably stick to the constituents of the weighing apparatus such as trough, pool hopper, weighing hopper and chutes, to cause various inconveniences as explained below.
For instance, a weighing error is caused however accurately the material is weighed in the weighing hoppers, if the weighed material is not completely discharged from the weighing hopper. In order to obviate this problem, recently, it has been proposed to coat the surfaces of the constituents contactable with the material with a parting agent such as Teflon, silicon or the like to permit an easy slip of the material. This countermeasure, however, is still unsatisfactory and cannot ensure the perfect separation of the sticking material.